Illumination system having two sensors, projection device comprising such an illumination system and illumination control method thereof

Abstract

The disclosure relates to an illumination system, a projection device and an illumination control method. The illumination system includes a first sensor, a second sensor and a control module. The first sensor receives a part of an excitation beam and a part of at least one converted beam scattered by a wavelength conversion module, so as to generate a first photoelectric signal. The second sensor receives a part of a first set of color light and a part of a second set of color light scattered by a filter module, so as to generate a second photoelectric signal. The control module generates a synchronization signal based on relative intensity changes of the first and second photoelectric signals. The synchronization signal is to synchronize the wavelength conversion module with the filter module, and the first set of color light and the second set of color light sequentially form an illumination beam.

What is claimed is: 
     
       1. An illumination system configured to provide an illumination beam, the illumination system comprising an excitation light source, a wavelength conversion module, a first sensor, a filter module, a second sensor and a control module, wherein
 the excitation light source is configured to emit an excitation beam; 
 the wavelength conversion module is located on a transmission path of the excitation beam, and has at least one wavelength conversion area configured to convert the excitation beam into at least one converted beam, 
 the first sensor is located beside and faces the transmission path of the excitation beam, and is configured to receive a part of the excitation beam and a part of the at least one converted beam that are scattered by the wavelength conversion module, so as to generate a first photoelectric signal; 
 the filter module is located on the transmission path of the excitation beam and the at least one converted beam, and has at least one filter area and a diffusion area, wherein the at least one filter area is configured to cause the at least one converted beam to form a first set of color light, and the diffusion area is configured to cause the excitation beam to form a second set of color light; 
 the second sensor is located beside and faces a transmission path of the first set of color light and the second set of color light, and is configured to receive a part of the first set of color light and a part of the second set of color light that are scattered by the filter module, so as to generate a second photoelectric signal; and 
 the control module is electrically connected to the first sensor and the second sensor, and is configured to receive the first photoelectric signal and the second photoelectric signal, wherein the control module generates a synchronization signal based on a relative intensity change of the first photoelectric signal and a relative intensity change of the second photoelectric signal, and the synchronization signal is transmitted to the wavelength conversion module and the filter module, so that the wavelength conversion module and the filter module are controlled to synchronize with each other, and the first set of color light and the second set of color light formed by the filter module sequentially form the illumination beam. 
 
     
     
       2. The illumination system according to  claim 1 , wherein the control module determines whether the at least one wavelength conversion area has entered an irradiation range of the excitation beam or not based on the relative intensity change of the first photoelectric signal, and determines whether the at least one filter area has entered an irradiation range of the at least one converted beam or not based on the relative intensity change of the second photoelectric signal. 
     
     
       3. The illumination system according to  claim 1 , wherein the control module is electrically connected to the excitation light source, and the second sensor comprises a chromaticity sensor, wherein the control module determines whether color coordinates to which the second photoelectric signal corresponds in chromaticity coordinates are expected values or not, and if not, the control module generates a current control signal, and the current control signal is transmitted to the excitation light source to adjust light intensity of the excitation beam. 
     
     
       4. The illumination system according to  claim 1 , wherein the wavelength conversion module further has a non-conversion area, and the wavelength conversion module further comprises a first substrate, at least one wavelength conversion layer and a first driving device, wherein
 the at least one wavelength conversion layer is disposed on the first substrate and is disposed corresponding to the at least one wavelength conversion area; 
 the first driving device is configured to drive the first substrate to rotate, and when the first substrate rotates, the at least one wavelength conversion area and the non-conversion area enter an irradiation range of the excitation beam during different periods. 
 
     
     
       5. The illumination system according to  claim 4 , wherein the filter module comprises a second substrate, at least one filter layer, a diffusion layer and a second driving device, wherein
 the at least one filter layer is disposed on the second substrate and is disposed corresponding to the at least one filter area; 
 the diffusion layer is disposed on the second substrate and is disposed corresponding to the diffusion area; 
 the second driving device is configured to drive the second substrate to rotate, wherein when the second substrate rotates, the at least one filter area enters an irradiation range of the at least one converted beam during different periods, and the diffusion area enters the irradiation range of the excitation beam during different periods. 
 
     
     
       6. The illumination system according to  claim 5 , wherein the control module is electrically connected to the first driving device and the second driving device, the first driving device controls a rotation period of the first substrate based on the synchronization signal from the control module, and the second driving device controls a rotation period of the second substrate based on the synchronization signal from the control module. 
     
     
       7. The illumination system according to  claim 5 , wherein, based on the synchronization signal from the control module, the first driving device and the second driving device respectively control the at least one filter area to enter the irradiation range of the at least one converted beam when the at least one wavelength conversion area of the wavelength conversion module enters the irradiation range of the excitation beam. 
     
     
       8. The illumination system according to  claim 1 , further comprising:
 a light combining unit located between the excitation light source and the wavelength conversion module and located on the transmission path of the at least one converted beam and the excitation beam. 
 
     
     
       9. The illumination system according to  claim 1 , further comprising:
 a light homogenizing element located on the transmission path of the at least one converted beam to homogenize the at least one converted beam. 
 
     
     
       10. The illumination system according to  claim 1 , further comprising:
 a light homogenizing element located on the transmission path of the first set of color light and the second set of color light to homogenize the first set of color light and the second set of color light. 
 
     
     
       11. A projection device, comprising an illumination system, a light valve and a projection lens, wherein
 the illumination system is configured to provide an illumination beam, and comprises an excitation light source, a wavelength conversion module, a first sensor, a filter module, a second sensor and a control module, wherein
 the excitation light source is configured to emit an excitation beam; 
 the wavelength conversion module is located on a transmission path of the excitation beam, and has at least one wavelength conversion area configured to convert the excitation beam into at least one converted beam, 
 the first sensor is located beside and faces the transmission path of the excitation beam, and is configured to receive a part of the excitation beam and a part of the at least one converted beam that are scattered by the wavelength conversion module, so as to generate a first photoelectric signal; 
 the filter module is located on the transmission path of the excitation beam and the at least one converted beam, and has at least one filter area and a diffusion area, wherein the at least one filter area is configured to cause the at least one converted beam to form a first set of color light, and the diffusion area is configured to cause the excitation beam to form a second set of color light; 
 the second sensor is located beside and faces a transmission path of the first set of color light and the second set of color light, and is configured to receive a part of the first set of color light and a part of the second set of color light that are scattered by the filter module, so as to generate a second photoelectric signal; 
 the control module is electrically connected to the first sensor and the second sensor, and is configured to receive the first photoelectric signal and the second photoelectric signal, wherein the control module generates a synchronization signal based on a relative intensity change of the first photoelectric signal and a relative intensity change of the second photoelectric signal, and the synchronization signal is transmitted to the wavelength conversion module and the filter module, so that the wavelength conversion module and the filter module are controlled to synchronize with each other, and the first set of color light and the second set of color light formed by the filter module sequentially form the illumination beam; 
 
 the light valve is located on a transmission path of the illumination beam and is configured to convert the illumination beam into an image beam; and 
 the projection lens is located on a transmission path of the image beam and is configured to cause the image beam to form a projection beam. 
 
     
     
       12. The projection device according to  claim 11 , wherein the control module determines whether the at least one wavelength conversion area has entered an irradiation range of the excitation beam or not based on the relative intensity change of the first photoelectric signal, and determines whether the at least one filter area has entered an irradiation range of the at least one converted beam or not based on the relative intensity change of the second photoelectric signal. 
     
     
       13. The projection device according to  claim 11 , wherein the control module is electrically connected to the excitation light source, and the second sensor comprises a chromaticity sensor, wherein the control module determines whether color coordinates to which the second photoelectric signal corresponds in chromaticity coordinates are expected values or not, and if not, the control module generates a current control signal, and the current control signal is transmitted to the excitation light source to adjust light intensity of the excitation beam. 
     
     
       14. The projection device according to  claim 11 , wherein, based on the synchronization signal from the control module, a first driving device of the wavelength conversion module and a second driving device of the filter module respectively control the at least one filter area to enter an irradiation range of the at least one converted beam when the at least one wavelength conversion area of the wavelength conversion module enters an irradiation range of the excitation beam. 
     
     
       15. The projection device according to  claim 11 , wherein the control module is electrically connected to the light valve, and the light valve modulates the illumination beam based on the synchronization signal from the control module, so as to form the image beam. 
     
     
       16. The projection device according to  claim 11 , further comprising:
 a light homogenizing element located on the transmission path of the at least one converted beam to homogenize the at least one converted beam. 
 
     
     
       17. The projection device according to  claim 11 , further comprising:
 a light homogenizing element located on the transmission path of the first set of color light and the second set of color light to homogenize the first set of color light and the second set of color light, wherein the light homogenizing element is located between the filter module and the light valve. 
 
     
     
       18. An illumination control method configured to control an illumination system in a projection device, the illumination system comprising an excitation light source, a wavelength conversion module, a first sensor, a filter module and a second sensor, the excitation light source being configured to emit an excitation beam, the wavelength conversion module being located on a transmission path of the excitation beam and being configured to convert the excitation beam into at least one converted beam, the first sensor being located beside and faced the transmission path of the excitation beam, the filter module being located on the transmission path of the excitation beam and the at least one converted beam and being configured to cause the at least one converted beam to form a first set of color light and to cause the excitation beam to form a second set of color light, and the second sensor being located beside and faced a transmission path of the first set of color light and the second set of color light, wherein the illumination control method comprises:
 sensing, by the first sensor, a part of the excitation beam and a part of the at least one converted beam that are scattered by the wavelength conversion module, so as to generate a first photoelectric signal; 
 sensing, by the second sensor, a part of the first set of color light and a part of the second set of color light that are scattered by the filter module, so as to generate a second photoelectric signal; 
 generating a synchronization signal based on a relative intensity change of the first photoelectric signal and a relative intensity change of the second photoelectric signal; and 
 transmitting the synchronization signal to the wavelength conversion module and the filter module, so as to control the wavelength conversion module and the filter module to synchronize with each other, and to cause the first set of color light and the second set of color light formed by the filter module to sequentially form an illumination beam. 
 
     
     
       19. The illumination control method according to  claim 18 , further comprising:
 determining whether at least one wavelength conversion area of the wavelength conversion module has entered an irradiation range of the excitation beam or not based on the relative intensity change of the first photoelectric signal, and determining whether at least one filter area of the filter module has entered an irradiation range of the at least one converted beam or not based on the relative intensity change of the second photoelectric signal. 
 
     
     
       20. The illumination control method according to  claim 19 , further comprising:
 based on the synchronization signal, controlling the at least one filter area to enter the irradiation range of the at least one converted beam when the at least one wavelength conversion area of the wavelength conversion module enters the irradiation range of the excitation beam. 
 
     
     
       21. The illumination control method according to  claim 18 , further comprising:
 determining whether color coordinates to which the second photoelectric signal corresponds in chromaticity coordinates are expected values or not, and if not, generating a current control signal; and 
 transmitting the current control signal to the excitation light source to adjust light intensity of the excitation beam. 
 
     
     
       22. The illumination control method according to  claim 8 , wherein the projection device comprises a light valve, and the illumination control method further comprises:
 transmitting the synchronization signal to the light valve, and modulating the illumination beam by the light valve based on the synchronization signal, so as to form an image beam.